Chapter Probabilistic Slope Stability Analysis for Embankment Dams Yijiang Zhang, Enyue Ji and Weiwei Xu Abstract Slope instability is one of the most common forms of dam failure. The commonly used slope stability analysis methods ignore the uncertainty and randomness of dam materials, which may overestimate the stability of dams. In this chapter, a deterministic slope stability analysis based on strength reduction finite- element method is introduced first. After that, the slope is investigated using simple probabilistic concepts and classical slope stability techniques, and the shear strength is treated as a single random variable. Further, the random finite-element method (RFEM) is shown, in which spatial correlation and local averaging are illustrated in detail. Finally, the RFEM is applied to slope stability risk assessment, and the results can lead to higher probabilities of failure. Keywords: slope stability, finite element, probabilistic methods, dam failure, risk assessment 1. Introduction Slope instability is one of the most common forms of dam failure. Traditional slope stability analysis methods mainly depend on deterministic analysis, including limit equilibrium analysis and finite-element (FE) analysis. Equilibrium methods mainly include the ordinary method of slices, Bishop’ s modified method, force equilibrium methods, Janbu’ s generalized procedure of slices, Morgenstern and Price’ s method, and Spencer’ s method. All the equilibrium methods assume that the soil can be divided into slices, which is an artificial distinction. This assumption is the main characteristic that distinguishes different limit equilibrium methods. The main advantage of equilibrium methods is that they involve relatively simpler calculation, which leads to wide use [1–4]. While the finite element method is another powerful approach for slope stability analysis, it can better reflect the stress–strain relationship of soils than the equilib- rium methods. Slope failure in the finite-element model occurs naturally through the area in which the shear strength of the soil is insufficient to resist the shear stresses. There are several advantages of a FE approach to slope stability analysis over traditional limit equilibrium methods: (a) there is no assumption about the shape or location of the failure surface, (b) there are no slices and slice side forces, and (c) the FE method is able to monitor progressive failure up to and including overall shear failure [5, 6]. For a practical slope, not only the stress–strain relationship of soils but also the uncertainty of soil properties should be taken into consideration. 1
Probabilistic Slope Stability Analysis for Embankment Dams
Jun 30, 2023
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Related Documents
